Jersey calf performance in response to high-protein, high-fat liquid feeds with varied fatty acid profiles: Blood metabolites and liver gene expression

Abstract

Most available Jersey calf milk replacers (CMR) use edible lard as the primary fat source, which lacks medium-chain fatty acids (MCFA). However, Jersey cow milk consists of over 10% MCFA. The objective of this trial was to determine whether altering the fatty acid profile of CMR by increasing the amount of MCFA would alter liver lipid infiltration, liver gene expression, and blood metabolites when fed to Jersey calves. Fifty Jersey calves were fed 1 of 4 diets: pasteurized saleable whole milk (pSWM) from Jersey cows [27.9% crude protein (CP), 33.5% fat, dry matter (DM) basis]; CMR containing 100% of fat as edible lard (100:00; 29.3% CP, 29.1% fat, DM basis); CMR containing 20% of fat as coconut oil (CO; 80:20; 28.2% CP, 28.0% fat); or CMR containing 40% of fat as CO (60:40; 28.2% CP, 28.3% fat). Liquid diet DM intake averaged 0.523, 0.500, 0.498, and 0.512 kg/d for pSWM, 100:00, 80:20, and 60:40, respectively. Calves were fed their assigned liquid diet daily at 0600 and 1800 h from 2 d of age until 7 wk of age, and once daily until 8 wk of age. Calves were taken off trial at 9 wk of age. Calves had access to water and grain (23.8% CP, 2.71% fat, DM basis). Grain DM intake averaged 0.386, 0.439, 0.472, and 0.454 kg/d for pSWM, 100:00, 80:20, and 60:40, respectively. Liver biopsy cores were obtained from 15 calves at 42 d of age (pSWM, n=4; 100:00, n=4; 80:20, n=3; 60:40, n=4) and from 4 baseline calves <2d of age. Liver biopsy cores were used for histological appraisal of lipid infiltration and gene expression analyses of short-, medium-, and long- chain acyl-coenzyme A dehydrogenases, sterol regulatory element binding transcription factor 1, acetyl coenzyme A carboxylase, and fatty acid synthase. Lipid infiltration and expression of selected genes were not different among diets. After an overnight fast, weekly blood samples were taken immediately before feeding at 0600 h via jugular venipuncture in all calves. Serum and plasma obtained from blood samples were used in the analyses of total protein, glucose, triglycerides, nonesterified fatty acids, and plasma urea nitrogen (PUN). Nonesterified fatty acids and PUN were the only blood metabolites affected solely by diet. Nonesterified fatty acids decreased in a linear manner with increased dietary CO inclusion. Calves fed pSWM had higher PUN than calves fed 80:20. In this trial, altering the fatty acid profile of CMR with the addition of medium-chain fatty acids from CO had minimal effects on liver lipid infiltration, liver gene expression, and blood metabolites when fed to Jersey calves.

Effect of medium-chain fatty acids on growth, health, and immune response of dairy calves

“…Also, MCFA MR contained slightly less fat (% of DM) compared with CON, which could be influencing the lower serum NEFA in MCFA calves. A prior study conducted using Jersey calves observed that fasting serum NEFA concentrations decreased as dietary MCFA increased (Swank et al, 2013), which is in agreeance with the current study. Another potential contributor for reduced NEFA concentrations at d 42 for MCFA calves is the numerical increase in starter intake for these calves.…”

Macronutrient and amino acids composition of milk replacers for dairy calves

“…The ether extract and crude protein content of the MR sampled are below those observed in MR commercialized in countries with a more developed dairy industry (Table 1). According to Swank et al (2013), feeding MR with CP and EE content lower than 20%, as most of the products sampled in this study, may negatively affect dairy calves' performance. Similarly, Bascom et al (2007) showed that weight gain and feed efficiency are lower for calves fed with milk replacer with CP and EE of 20%, as compared to animals fed whole milk or replacer with higher CP associated with EE lower than 20 %.…”

Pregnant Cows and Heifers Blood Profile Comparison

“…Female body is bearing the heaviest stress during pregnancy -all systems and organs endure overload not only during pregnancy, but also after -during calving and ongoing lactation [2,13]. Dairy yield and the calf condition depend on health and wellbeing of the cow [15]. That is why it is essential to pay attention to the cows and heifers during the last trimester of pregnancy.…”